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# GenerationSchema

A type that describes the properties of an object and any guides
on their values.

```
struct GenerationSchema
```

## Overview

Generation schemas guide the output of a language model to deterministically
ensure the output is in the desired format.

## Topics

### Creating a generation schema

[`init(root:dependencies:)`](/documentation/FoundationModels/GenerationSchema/init(root:dependencies:))

Creates a schema by providing an array of dynamic schemas.

[`init(type:description:anyOf:)`](/documentation/FoundationModels/GenerationSchema/init(type:description:anyOf:))

Creates a schema for a string enumeration.

[`init(type:description:properties:)`](/documentation/FoundationModels/GenerationSchema/init(type:description:properties:))

Creates a schema by providing an array of properties.

[`init(type:description:representNilExplicitlyInGeneratedContent:properties:)`](/documentation/FoundationModels/GenerationSchema/init(type:description:representNilExplicitlyInGeneratedContent:properties:))

Creates a schema by providing an array of properties.

[`GenerationSchema.Property`](/documentation/FoundationModels/GenerationSchema/Property)

A named, strongly typed member of an object type with an optional description and guides.

### Accessing the name

[`name`](/documentation/FoundationModels/GenerationSchema/name)

The name of this generation schema.

### Errors

[`GenerationSchema.SchemaError`](/documentation/FoundationModels/GenerationSchema/SchemaError)

An error that occurs when there is a problem creating a generation schema.


---

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